Older men with gout are almost four times as likely to have osteoarthritis of the knee, research shows.

The findings suggest that urate lowering trials in OA may be worth considering in the future, say the researchers from New York University.

Of 115 men aged 55 to 85 years 29 had gout, 31 had elevated uric acid levels but no gout symptoms. A control group of 55 men had normal uric acid levels.

Knee osteoarthritis was assessed using X-rays, physical examinations and questionnaires.  Ultrasound was used to detect tophi deposits.

Knee osteoarthritis was diagnosed in 68% of gout patients, 52% of men with elevated uric acid and 28% of controls (P=0.017 gout vs control), the researchers reported in the Journal of Clinical Rheumatology.

Subjects with sonographically detected monosodium urate crystal deposition on cartilage were more likely to have OA than those without (60.0 vs 27.5%, P = 0.037), with crystal deposition at the first metatarsophalangeal joints correlating most closely with OA knee involvement.

The presence of gout was associated with more severe structural knee OA (defined as higher KL grades and more bilateral knee OA involvement), they found.

The association between gout and OA might represent a cause-and-effect relationship or might result from a common risk factor shared by both diseases such as obesity and older age.

However, the fact that the association persisted after accounting for BMI suggests obesity is insufficient to fully explain association, they said.

“The possibility that gout and/or AH might be a factor contributing to future OA progression, together with the fact that both AH and gout can be managed using approved urate-lowering therapies, suggests that trials of urate lowering and/or gout treatment optimization for OA management may deserve future consideration,” they concluded.